Adding generic callback interfaces.

mojo/tools/generate_java_callback_interfaces.py

Index: mojo/tools/generate_java_callback_interfaces.py
diff --git a/mojo/tools/generate_java_callback_interfaces.py b/mojo/tools/generate_java_callback_interfaces.py
new file mode 100644
index 0000000000000000000000000000000000000000..f19ef6d0bd5b621193e259ad24b61f83b891e640
--- /dev/null
+++ b/mojo/tools/generate_java_callback_interfaces.py
@@ -0,0 +1,60 @@
+"""Generate the org.chromium.mojo.bindings.Callbacks interface"""
+
+import argparse
+import sys
+
+CALLBACK_TEMPLATE = ("""
+    /**
+      * A generic %d-argument callback.
+      *
+      * %s
+      */
+    interface Callback%d<%s> {
+        /**
+          * Call the callback.
+          */
+        public void call(%s);
+    }
+""")
+
+INTERFACE_TEMPLATE = (
+"""// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This file was generated using
+//     mojo/tools/generate_java_callback_interfaces.py
+
+package org.chromium.mojo.bindings;
+
+/**
+ * Contains a generic interface for callbacks.
+ */
+public interface Callbacks {
+%s
+}
+""")
+
+def GenerateCallback(nb_args):
+   params = '\n      * '.join(
+       ['@param <T%d> the type of argument %d.' % (i+1, i+1)
+        for i in xrange(nb_args)])
+   template_parameters = ', '.join(['T%d' % (i+1) for i in xrange(nb_args)])
+   callback_parameters = ', '.join(['T%d arg%d' % ((i+1), (i+1))
+                                    for i in xrange(nb_args)])
+   return CALLBACK_TEMPLATE % (nb_args, params, nb_args, template_parameters,
+                               callback_parameters)
+
+def main():
+  parser = argparse.ArgumentParser(
+      description="Generate org.chromium.mojo.bindings.Callbacks")
+  parser.add_argument("max_args", nargs=1, type=int,
+      help="maximal number of arguments to generate callbacks for")
+  args = parser.parse_args()
+  max_args = args.max_args[0]
+  print INTERFACE_TEMPLATE % ''.join([GenerateCallback(i+1)
+                                      for i in xrange(max_args)])
+  return 0
+
+if __name__ == "__main__":
+  sys.exit(main())